G
G.A. Sanchez-Azofeifa
Researcher at University of Alberta
Publications - 17
Citations - 1771
G.A. Sanchez-Azofeifa is an academic researcher from University of Alberta. The author has contributed to research in topics: Tropical and subtropical dry broadleaf forests & Leaf area index. The author has an hindex of 16, co-authored 17 publications receiving 1643 citations.
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Journal ArticleDOI
Validation of global moderate-resolution LAI products: a framework proposed within the CEOS land product validation subgroup
Jeffrey T. Morisette,Frédéric Baret,Jeffrey L. Privette,Ranga B. Myneni,Jaime Nickeson,Sébastien Garrigues,N.V. Shabanov,Marie Weiss,Richard Fernandes,Sylvain G. Leblanc,Margaret Kalacska,G.A. Sanchez-Azofeifa,M. Chubey,Benoit Rivard,Pauline Stenberg,Miina Rautiainen,Pekka Voipio,Terhikki Manninen,A. N. Pilant,T.E. Lewis,John S. Iiames,Roberto Colombo,Michele Meroni,Lorenzo Busetto,Warren B. Cohen,David P. Turner,E.D. Warner,G.W. Petersen,Guenther Seufert,Robert B. Cook +29 more
TL;DR: In this paper, the authors describe the main components of this international validation effort, including the current participants, their ground LAI measurements and scaling techniques, and the metadata and infrastructure established to share data.
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Species composition, similarity and diversity in three successional stages of a seasonally dry tropical forest
Margaret Kalacska,G.A. Sanchez-Azofeifa,Julio Calvo-Alvarado,Mauricio Quesada,Benoit Rivard,Daniel H. Janzen +5 more
TL;DR: The floristic composition, species diversity, similarity and richness among three stages of forest regeneration, and the influence of past land use and the frequency of anthropogenic disturbances on species composition in a seasonally dry tropical forest in northwestern Costa Rica are described.
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Continuous wavelet analysis for the detection of green attack damage due to mountain pine beetle infestation
TL;DR: In this paper, the authors used a continuous wavelet transform to detect green attack damage in lodgepole pine needles by means of hyperspectral measurements, particularly via continuous wavelets analysis.
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Ecological fingerprinting of ecosystem succession: Estimating secondary tropical dry forest structure and diversity using imaging spectroscopy
Margaret Kalacska,G.A. Sanchez-Azofeifa,Benoit Rivard,Terry Caelli,H. Peter White,Julio Calvo-Alvarado +5 more
TL;DR: In this article, the authors evaluated the use of EO-1 Hyperion hyperspectral satellite imagery for mapping structure and floristic diversity in a Neotropical tropical dry forest as a way of assessing a region's ecological fingerprint.
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Hyperspectral discrimination of tropical dry forest lianas and trees: Comparative data reduction approaches at the leaf and canopy levels
Margaret Kalacska,Stephanie A. Bohlman,Stephanie A. Bohlman,G.A. Sanchez-Azofeifa,K.L. Castro-Esau,Terry Caelli +5 more
TL;DR: In this paper, a dataset of spectral signatures (leaf level) of tropical dry forest trees and lianas and an airborne hyperspectral image (crown level) are used to test three hypersensorral data reduction techniques (principal component analysis, forward feature selection and wavelet energy feature vectors) along with pattern recognition classifiers to discriminate between the spectral signatures of liansas and trees.